Vinylcarbazole

Photochemical syntheses of carbazoles and carbazole alkaloids from diphenylamine and other substrates have been discussed previously by 

Chakraborty (18) as well as by Joule (63). Recently de Mayo et al. (i) showed that vinyl carbazole (171) on photochemical reaction in CdS dispersed medium undergoes dimerisation leading to a cyclobutone (172) to which two carbazole units are attached. 

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Unusual ir-complex compounds were obtained when reacting with Yb(fod)3 and Ag(fod) with 9-vinylcarbazole (83PJC1393). The NMR spectrum of 9-vinylcarbazole in the presence of Yb(fod)3 + Ag(fod) as the lanthanide shift... 

Suppression of the aggregate emission is possible in two quite different ways. At first, the aggregate emission could be almost completely shut out by simply diluting the LPPP 12 with a matrix polymer. LEDs with 1% LPPP 12 in poly(9-vinylcarbazole) PVK as emitter material are characterized by a pure blue light emission with a quantum efficiency of ca. 0.15% in single-layer configuration (lTO/1% LPPP 12 in PVK/Ca) 135],... 

Reaction of 9-vinylcarbazole with bromine in benzene or ethanol gave the 3,6-dibromo derivative [84AHC(35)83]. Pyridinium bromide perbro-mide gave a 72% yield of the 3-bromo derivative of 2,4-dimethoxycarba-zole. With other reagents mixtures of 3- and 5-bromo-, 3,5- and 3,7-dibromo products were formed. The 5-bromo- and 3,6-dibromo- compounds rearranged quantitatively to the 3- and 3,7-isomers [92JCR(S)2]. 

C Zhang, H von Seggern, K Pakbaz, B Kraabel, H-W Schmidt, and AJ Heeger, Blue electroluminescent diodes utilizing blends of poly(p-phenylphenylene vinylene) in poly(9-vinylcarbazole), Synth. Met., 62 35—40, 1994. 

There are several examples of the 1,2-elimination of hydrogen chloride from 9-(2-chloroethyl)carbazoles, using potassium hydroxide in ethanol, generating the 9-vinylcarbazoles. 3-Dimethylamino-9-(2-hydroxyethyl) carbazole comparably lost water on base treatment. Dimethylamine displacement of halogen, then amine N-oxide formation and elimination was utilized to produce 9-alkenylcarbazoles with four, five, and six carbon atoms from the corresponding cu-haloalkyl carbazoles. ... 

The head-to-head trans-cyclorimer 92 of 9-vinylcarbazole (see Section II,C,2) undergoes C—C bond fission by a one-electron oxidative process on treatment with cerium ammonium nitrate or tris-(p-bromophenyl)ammo-niumyl hexachloroantimonate in methanol giving 93. ... 

Aqueous acid has been utilized to cleave the enamine-like C—N bond of the 9-alkenylcarbazoles 94 and 95 ° and the products 82 of alkylation of the anions of 9-allyIcarbazoles hydrated ferric nitrate was used to remove the vinyl group from 3-halo-9-vinylcarbazoles, Strong base... 

Electrophilic addition to 9-vinylcarbazole occurs in the Markovnikov sense, thus hydrogen chloride,hydrogen bromide,chlorine, and bromine in carbon tetrachloride, and iodine chloride in pyridine are recorded as adding with initial electrophilic attack at the methylene. Mercuric acetate in methanol gave 9-(2-acetoxymercuri-l-methoxyethyl)carbazole. Although 9-vinylcarbazole gave an iodohydrin, comparable reaction with methanolic sodium hypochlorite led to 9-(2-chlorovinyl)carbazole. Catalytic reduction of the latter produced 9-(2-chloroethyl)carbazole. Tri-phenyltin hydride gave 96. ... 

The acetoxy group of 9-(l-acetoxyethyl)carbazole is easily displaced with alcohols. Easy displacement of a similarly situated halogen can be achieved, as has been noted before (see Section II,C,2) thus methanol converts 9-(l-chloro-2-iodoethyl)carbazole to 9-(2-iodo-l-methoxyethyI) car-bazole. Elimination of acetic acid or ethanol by strongly heating 9-(l-acetoxyalkyl)- or 9-(l-ethoxyalkyl)carbazoles gives 9-vinylcarbazoles. In the absence of acid, ( )-alkenes are produced, but acid catalysis leads to a mixture of E and Z isomers. Acetyl chloride in pyridine also effects ethanol elimination. ... 

Bromine in benzene or ethanol brings about 3,6-disubstitution of 9-vinylcarbazole as well as electrophilic addition to the double bond. A good yield of 3-iodocarbazole results from the use of iodine-iodic acid in acetic acid at iodine chloride in acetic acid caused 3,6-di-... 

The photoinduced electron transfer (PET) initialed cyclodimerization was first studied with 9-vinylcarbazole as substrate1 and characterized mechanistically as a cation radical chain reaction.2 The overall reaction sequence3-4 consists of a) excitation of an electron acceptor (A), b) electron transfer from the alkene to the excited acceptor (A ) with formation of a radical ion pair, c) addition of the alkene radical cation to a second alkene molecule with formation of a (dimeric) cation radical, and d) reduction of this dimeric cation radical by a third alkene molecule with formation of the cyclobutanc and a new alkene cation radical. Steps c) and d) of the sequence are the chain propagation steps. The reaction sequence is shown below. 

The detection of contamination with mercury is a very serious issue due to the extreme toxicity and ease of reaction of this heavy metal. Mercury is commonly used in many everyday applications, such as thermometry, barometry or scientific apparatus. Therefore, it is important to note the development of a fluorescent IIP membrane for detection of mercury [63], This membrane was based on the combination of two fluorescent functional monomers, namely 4-vinyl pyridine and 9-vinylcarbazole. Binding of Hg2+ was proposed to be based on complexation of the metal ion with lone pairs of both pyridine and carbazole. The IIP membrane was capable of recognizing Hg2+in the linear range of concentrations from 5 x 10 7 to 1 x 10 4 M. Selectivity of the chemosensor was studied for a wide group of possible competitive ions and the chemosensor responded to all of them in the presence of a fixed amount of Hg2+ at 1 x 10 5 M. Nevertheless, the highest influence on recognition properties was observed in the presence of Cu2+ (4.87%) and Pb2+ (4.57%), which are still acceptable values for the successful detection of Hg2+. This progress stimulates further development of the MIP detection of ions. 

Place 9-vinylcarbazole (1.0 g, 5.0 mmol) in the reaction vessel together with anhydrous toluene (1 ml). 

The soluble metalloporphyrin-containing polymers are formed by the copolymerization of MM A or 4-VP with macrocyclic MCM — an interaction product of acrylic acid chloride with tetra-p-aminophenylporphyrinate acetate manganese [96]. Copolymers obtained by the radical copolymerization of acryloyl derivatives of cobalt phthalocyanine with 9-vinylcarbazole [97] should also be mentioned. 

Despite the reactivity of carbazole cation-radicals, that of 9-ethylcarbazole has been trapped by nucleophiles, e.g., I", NO2,475 Thus, iodo and nitro derivatives of 9-ethylcarbazole result, along with 9,9 -diethyl-3,3 -bicarbazole, when 9-ethylcarbazole is oxidized by iodine in the presence of iodide and nitrite.473 Oxidation in the absence of nucleophiles, e.g., by nitrosonium tetrafluoroborate, permits the synthesis of the cation-radical fluoroborate salts of the 3,3 -bicarbazoles476 The reactivity of the cation-radical of 9-vinylcarbazole has been reviewed recently.11,477... 

C13H29N tert-amyl-tert-octylamine 150285-07-7 473.15 31.140 1,2 26828 C14H11N 9-vinylcarbazole 1484-13-5 566.15 50.275 2... 

Hawker et al. [95] and Fukuda et al. [96] both reported on the copolymerization of St with various monomers in 1996. Hawker reported copolymerizations with nBA, MMA, and p-chloromethylstyrene (CMSt), while Fukuda focused on several acrylates, 9-vinylcarbazole, and acrylonitrile (AN), and succeeded in preparing block-random copolymers of St with AN (details below). Neither group found the polymerizations to be well-controlled when low concentrations of St were present in the comonomer feed. However, since then, NMP has been used extensively to prepare copolymers. Pozzo et aL copolymerized St with 4-vinyl pyridine (VP), initiated by benzoyl peroxide (BPO) and using TEMPO as the radical mediator [97]. After purification, the copolymer was reacted with spiro [fluorenecyclopropene] to prepare photochromic copolymers with controlled molecular weights (Scheme 6). 

Excimer formation and its potential applications for polymers continues to be widely studied. Poly(N-vinylcarbazole) continues to be investigated with the monomer exhibiting yet again a new emission below 400 nm assigned to a second excimer state similar to that seen in the homopolymer. Poly(3,6-di-tert-butyl-9-vinylcarbazole) has been found to give unique sandwich excimer formation due to syndiotactic diads while the effect of hydrostatic pressure on intramolecular excimer formation for meso-2,4-di-N-carbazolylpentane dissolved in poly(propylene oxide) has indicated that the compressibility of free volume cannot be considered to be constant. A new scheme has been proposed to... 

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